{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T03:27:41Z","timestamp":1771558061213,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,27]],"date-time":"2022-07-27T00:00:00Z","timestamp":1658880000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Portuguese National Funding Agency (FCT)","doi-asserted-by":"publisher","award":["UIDB\/00068\/2020"],"award-info":[{"award-number":["UIDB\/00068\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Portuguese National Funding Agency (FCT)","doi-asserted-by":"publisher","award":["PTDC\/FIS-AQM\/31281\/2017"],"award-info":[{"award-number":["PTDC\/FIS-AQM\/31281\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"University of Innsbruck, Austria","award":["UIDB\/00068\/2020"],"award-info":[{"award-number":["UIDB\/00068\/2020"]}]},{"name":"University of Innsbruck, Austria","award":["PTDC\/FIS-AQM\/31281\/2017"],"award-info":[{"award-number":["PTDC\/FIS-AQM\/31281\/2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The geometrical effect of chlorine atom positions in polyatomic molecules after capturing a low-energy electron is shown to be a prevalent mechanism yielding Cl2\u2212. In this work, we investigated hexachlorobenzene reduction in electron transfer experiments to determine the role of chlorine atom positions around the aromatic ring, and compared our results with those using ortho-, meta- and para-dichlorobenzene molecules. This was achieved by combining gas-phase experiments to determine the reaction threshold by means of mass spectrometry together with quantum chemical calculations. We also observed that Cl2\u2212 formation can only occur in 1,2-C6H4Cl2, where the two closest C\u2013Cl bonds are cleaved while the chlorine atoms are brought together within the ring framework due to excess energy dissipation. These results show that a strong coupling between electronic and C\u2013Cl bending motion is responsible for a positional isomeric effect, where molecular recognition is a determining factor in chlorine anion formation.<\/jats:p>","DOI":"10.3390\/molecules27154820","type":"journal-article","created":{"date-parts":[[2022,7,28]],"date-time":"2022-07-28T03:21:16Z","timestamp":1658978476000},"page":"4820","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Sensing the ortho Positions in C6Cl6 and C6H4Cl2 from Cl2\u2212 Formation upon Molecular Reduction"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1996-9925","authenticated-orcid":false,"given":"Sarvesh","family":"Kumar","sequence":"first","affiliation":[{"name":"Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Campus de Caparica, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5663-1085","authenticated-orcid":false,"given":"Jos\u00e9","family":"Romero","sequence":"additional","affiliation":[{"name":"Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Campus de Caparica, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal"},{"name":"Institut f\u00fcr Ionenphysik und Angewandte Physik, Leopold-Franzens Universit\u00e4t Innsbruck, Technikerstra\u00dfe 25, 6020 Innsbruck, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3112-5597","authenticated-orcid":false,"given":"Michael","family":"Probst","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Ionenphysik und Angewandte Physik, Leopold-Franzens Universit\u00e4t Innsbruck, Technikerstra\u00dfe 25, 6020 Innsbruck, Austria"},{"name":"School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Rayong 21210, Thailand"}]},{"given":"Thana","family":"Maihom","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Liberal Arts and Science, Kamphaeng Saen Campus, Kasetsart University, Nakhon Pathom 73140, Thailand"}]},{"given":"Gustavo","family":"Garc\u00eda","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica Fundamental, Consejo Superior de Investigaciones Cient\u00edficas, Serrano 113-bis, 28006 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2696-1152","authenticated-orcid":false,"given":"Paulo","family":"Lim\u00e3o-Vieira","sequence":"additional","affiliation":[{"name":"Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Campus de Caparica, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/S0045-6535(00)00186-7","article-title":"Global hexachlorobenzene emissions","volume":"43","author":"Bailey","year":"2001","journal-title":"Chemosphere"},{"key":"ref_2","unstructured":"U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry, Division of Toxicology and Human Health Sciences, Environmental Toxicology Branch (2015). 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